Press detecting touch panel and display device

Abstract

A press detecting touch panel that includes a housing defining an opening, a piezoelectric film, and a holding member which holds the piezoelectric film within the opening. An entire periphery of the holding member is fixed to the housing such that the holding member covers the opening, and a first cross sectional shape along a first direction of the holding member is different than a second cross sectional shape along a second direction of the holding member.

The invention claimed is: 
     
       1. A press detecting touch panel comprising:
 a housing defining an opening; 
 a piezoelectric film; and 
 a holding member which holds the piezoelectric film within the opening, an entire periphery of the holding member being fixed to the housing such that the holding member covers the opening, a first cross sectional shape along a first direction of the holding member is different than a second cross sectional shape along a second direction of the holding member, the first direction and the second direction being orthogonal to each other, and a first curvature of a first main surface of the holding member is different from a second curvature of a second main surface of the holding member, the first main surface and the second main surface opposing each other, and each of the first main surface and the second main surface extending perpendicular to a stacking direction of the housing, the piezoelectric film and the holding member, 
 wherein, when the holding member is bent by a pressing force applied to the first main surface thereof, a warp in a horizontal direction is less than a warp in a vertical direction of the holding member. 
 
     
     
       2. The press detecting touch panel according to  claim 1 , wherein the piezoelectric film is made of a uniaxially stretched chiral polymer. 
     
     
       3. The press detecting touch panel according to  claim 1 , wherein the holding member has a non-uniform thickness. 
     
     
       4. The touch panel according to  claim 1 , wherein a thickness of the holding member changes along at least one of the first direction and the second direction. 
     
     
       5. The press detecting touch panel according to  claim 1 , wherein
 the holding member comprises a plurality of laminated members, and 
 each of the plurality of laminated members has a different aspect ratio in a plan view of the press detecting touch panel. 
 
     
     
       6. The press detecting touch panel according to  claim 5 , wherein the plurality of laminated members include a first panel which is fixed to the housing and a second panel attached to the first panel, the second panel having a smaller area than the first panel in the plan view. 
     
     
       7. The press detecting touch panel according to  claim 1 , wherein a touch surface side of the holding member has a protrusion shape. 
     
     
       8. The press detecting touch panel according to  claim 1 , wherein the holding member has a square shape in a plan view of the press detecting touch panel. 
     
     
       9. The press detecting touch panel according to  claim 1 , wherein the holding member has a circular shape in a plan view of the press detecting touch panel. 
     
     
       10. A display device comprising:
 the press detecting touch panel according to  claim 1 ; and 
 a display unit within the housing.